Electric motor driven jig-saw unit



Sept. 2, 1952 T. R. BUSH 2,609,016

ELECTRIC MOTOR DRIVEN JIG-SAW UNIT Filed Aug. 5, 1949 2 SHEETS-SHEET 1 Z4 Bo I55 I34 24 In '6 44 4 as 36/ a4 46 4 6D as INVENTOR.

THEODORE R. Busu BY Sept; 2, 1952 T. R. BUSH 2,609,016

ELECTRIC MOTOR DRIVEN JIG-SAW UNIT Filed Aug. 5. 1949 2 SHEETS-SHEET 2 ll-Ill IN VEN TOR.

THIOOORE R. Busn ATTO Patented Sept. 2, 1952 UNITED STATES PATENT OFFICE Q 2,609,016 A I mlsornio Moron DRIVEN JId-sAw UNIT Theodore It. Bush, Royal Oak, Mich. Application August 3, 1949, Serial No. 108,273

. Thi invention relates to a motor driven woodworking machine and has particular reference to new and useful improvements in such machines.

It i a primary objectof the invention to provide a new and improved method of supplying a blast of air to the work piece which is supported upon the worktable of the machine so that such work piece will be kept free from sawdust, chips and other such material.

Another object of the invention is to provide in a machine of this type a compact unit wherein the electric driving motor and thereciprocating mechanism for the machine are mounted within a hollow base, thereby eliminating the usual belt and pulleysfound in machines of this typef Another object of the invention is to provide an improved universal mounting for the worktable of the machine. U

Other and further objects of the invention will be apparent from the following description and claims and will be understood by reference to the accompanying drawings, of which there are two sheets, which by way ofillustrationsho'w a preferred embodiment and the principles thereof and what I now consider to be'the best mode in which I have contemplated applying those principles. Other embodiments of the invention embodying the same or equivalent principles may be used and structural changes may be made as desired by those skilled in the art without departing from the present invention and the purview of the appended claims.

- In the drawings:

Fig. 1 is a side elevational view of the invention with certain portions broken away;

Fig. 2 is a front elevational view; 7

Fig. 3 is a. partial sectional view taken along the lines 33 of Fig. 1;

F g. 4. is a sectional View taken along the lines 2-4 of Fig. l;

Fig. 5 is a sectional view taken along the lines 5-5 of Fig. 2; 1 I

Fig. 6 is a sectional view taken along the lines 8-4 of Fig. 2; and

Fig. 7 is a fragmentary side elevation cith device showing the worktable tilted.

A woodworking machine of the type contemplated by this invention comprises a hollow cast iron base indicated generallyat Ill, a vertical column 12 and a horizontally extending arm I4, a universally mounted worktable [5, an electric motor l8, and reciprocating mechanism '26.

The vertical column I2 is supported on one end of the base [0 by means of bolts 22. The arm I4 is formed integrally with the vertical 2 Claims. (01. 143

column l2 and is arranged to overlie the worktable it. The electric motor l8 and the reciprocating mechanism 20 are bolted together and are secured within the hollow base It, thereby eliminating thenecessity for the usual belts and pulleys found in machines of this type. A toggle switch 2| is provided on'the base It for operation of the motor 18. The motor i8 and the mechanism 20 may be of any standard type which will permit rapid reciprocating movement of a plunger projecting from the mechanism 22. As is clearlyshown in Fig. 3, the plunger 22 of the reciprocating mechanism 20 projects vertically above the upper surface of the base Ill. The arm I4 is provided with means at the free end thereof cooperating with the plunger 22 for reciprocating a woodworking tool 24 through an opening 26 in the table l6 upon operation of the motor it.

As is best shown in Figs. 1, 3 and 7, the mounting means for the table It consists of a channelshaped member 28 which is seated upon a boss 3E3 onthe base ID. Brackets 32 and as are secured to the under side of the table it by means of screws 36 and nuts 38. The brackets 32 and 3c are apertured at 4D to accommodate the head 42 of a round-headed screw 44. The parallel slides 46 of the channel-shaped member 28 have apertures 48 in alignment with the holes 46 in the brackets 32 and 34. A nut 59 cooperates with the screw 44 to pivotally secure the brackets to the channel-shaped member28. The head 42 of the screw 44 is free to turn within the holes 40 provided in the brackets 32 and 34.

Bracket 34 is provided with an arcuate slot 52. A handle 54 is provided with athreaded portion 56 which cooperates with one of the sides 46 to secure the bracket 34 to the side 46. The handle 54 is provided witha pin 58 to facilitate adjustment of the handle 54. Thus it will be seen that when the handle 54 is tightened by means of the threaded portion 56, no movement or" the brackets 32 and 34 with respect to the channel member 28 will be permitted. v

A plate 60 is secured to the lower end of the bracket 34 and is provided with markings in degrees so that the table It maybe tilted to any desired angle from 0 to 45 and then secured at such tilted position by means of the handle 54. A pointer 62 is secured to the side 45 by means of a screw 64 and cooperates with the markings on the plate 62 so that the table may be accurately adjusted. I

The reciprocating mechanism 20 is provided with a plunger 22 which reciprocates through a bushing 65 which is rigidly secured to the mechanism 2B. A nut 68 is threadedly secured to the end of the bushing 06. The channel-shaped member 28 has a central opening 10 therein through which the neck- 12 of the nut 88 projects. As the nut 68 is threaded upon the bushing 68, it will be seen that the reciprocating mechanism 20 will be held tightly against the surface I4 of the base I0. The nut 68 provides the only means for mounting the reciprocating mechanism 20 and the electric ,motor I8 within the hollow base I0, and thus it will be seen that the motor I8 and the mechanism 20 may be easily removed if an repairs or adjustment is necessary.

The head 16 of the nut 68 when the nut 68 has been fully tightened on the bushing 88, is arranged to seat loosely on the bottom wall of the channel member 28 so that the member 28 may be rotated a complete 360 around the neck I2 of the nut 88. Setscrews 18 are provided to securely clamp the channel member 28 against the base I so that the table may be rotated to any angular position desired and then secured in such position by means of the screws I8.

It will be seen from the foregoing description that any desired position of the table I 6 may be obtained up to 45 of inclination by the simple loosening and then tightening of screws I8 and the handle 54. v

The arm I4 at the free end thereof is provided ing member I 32 are secured to the end of the tube I20 by means of a screw I34. The saw guide I is channel shaped in cross section and provided with an elongated slot I36 in the bottom wall so that the channel-shaped member I 30 may be adjusted toward or away from the woodworking tool 24. The work holding member I32 has a downwardly curved end I33, and a slot I is provided in the end I33 of the member I32. The end I33 straddles the woodworking tool 24 and is adapted to springably hold the work on the worktable I6 in any position of the table IS.

A circular guide I38 having an annular groove I is secured between the parallel sides of the channel member I30 by means of a pin I42. When a saw blade is used in the operation of the machine the channel member I30 may be moved v toward the blade by means of the elongated slot with a cylinder 80 and a piston member 82 which may be reciprocated within the cylinder80. The piston 82 and the plunger 22 are each provided with a chuck 84. The chucks 84 are secured to the piston 82 and the plunger 22 by means of screws 86. The chucks 84 are alsopr'ovided with aligned screws 88 for securing the end of a woodworking tool 24 within the chucks 84. The opening 88 in each of the chucks 84 is sufiiciently large to receive not only a saw blade as illustrated in the drawings, but other woodworking tools such as sanding sticks or files.

The piston 82 is provided with an enlarged head 92. A spring 94 is confinedbetween the head 92 and an annular shoulder 98 within the cylinder 80 so that the piston 82 is biased away from the plunger 22 thereby putting the proper amount of tension on the woodworking tool 24. The piston 82 is provided with a flat surface 88. A plate I00 is secured to the under side of the arm I4 by means of a screw I02, and the plate I00 cooperates with the fiat surface 98 to prevent rotation of the piston 82 within the cylinder 80.

The vertical column I2 and the arm- I4 are hollow, and a light socket I04 is secured Within the arm I4 adjacent the forward end thereof. A bulb I88 is provided for the socket I04 above an opening I08 in the arm I4. The bulb I06 is also operable by the toggle switch 2I. The cord II 0 for the bulb I05 extends through the hollow arm I4 and the vertical column I2 and through an opening I I2 in the base I0 to the toggle switch 2 I.

A hollow cap II 4 is secured to the upper end of the cylinder 80 and is provided with a neck I IS. A flexible hose I I8 is fitted over the neck lit, and a. hollow tube I20 is inserted into the other end of the hose II 8. The arm I4 is provided with a laterally extending boss I22 through which the tube I20 extends. A screw I24 having a head I26 is threaded into the boss I22 for detachably securing the tube I20 to the boss I22. The hose H8 and the tube I20 provide a duct I28 through which a blast of air may be forced upon reciprocating movement of the piston 82 within the cylinder 80. The lower end of the tube I 20 is provided with a saw guide I 30 and a work holddown I32. The saw guide I30 and the work hold- I36 until the back edge of the blade is seated within the groove I40 to provide a means for guiding the reciprocating movement of the blade and preventing the blade from becoming bent or distorted while in use.

The tube I20 i provided with an aperture I44 at the lower end thereof in communication with the duct I28. As the piston 82 moves upwardly Within thevcylinder 80, the air within the duct I28 will be compressed and a blast of air will be discharged through the aperture I44. The aperture I 44 is directed slightly downward so that the air discharged therefrom will be directed toward the bottom of the channel member I30. The parallel sides of the member I30 cooperate with the aperture I 44 to direct the blast of air downwardly through the elongated slot I36 and upon the work piece located on the table I6 so as to keep the work free from sawdust or chips. Since the tube I20 serves as an adjustable means for securing the saw guide I30 and work holding member I 32 and at the same time provides a means for conveying a blast of air to the work, it will be seen that no interference from the usual air hose and clamps therefor is present.

While I have illustrated and described a preferred embodiment of my invention, it is understood that this is capable of modification, and I therefore do not wish to be limited to the precise details set forth but desire to avail myself of such changes and alterations as fall within the purview of the following claims.

I claim:

1. In an electric motor driven woodworking machine, a hollow base provided with a horizontal surface having an opening therein, a bracket having a fiat portion provided with an opening and seated on said surface, a worktable mounted on said bracket, a drive unit arranged within said hollow base and comprising an electric motor and reciprocating mechanism driven thereby and secured thereto, said drive unit including an externally threaded bushing projecting upwardly through said openings in said base and said bracket, said reciprocating mechanism including a plunger reciprocable in said bushing for reciprocating a woodworking tool through an opening in said table upon operation of said motor, a nut threaded onto said bushing and having a reduced neck portion projecting through the opening in said bracket, said nut providing a means for securing said drive unit to said base, said flat portion of said bracket being arranged between said base and the head of said nut and being rotatable about said reduced portion of said nut, and other threaded means extending through said head of said nut and engageable with said fiat portion of said bracket for clamping said bracket against said base so as to prevent rotation of said bracket and table.

2. In an electric motor driven woodworking machine, a hollow base, a worktable, means for mounting said table on said base comprising a U-shaped bracket seated on said base, said table being pivotally secured to said bracket so as to permit tilting movement of said table, a drive unit arranged within said hollow base and comprising an electric motor and reciprocating mechanism driven thereby and secured thereto, said drive unit including a bushing projecting upwardly through said base and said bracket, said reciprocating mechanism including a plunger reciprocable in said bushing for reciprocating a woodworking tool through an opening in said table upon operation of said motor, threaded means engageable with said bushing for securing said drive unit to said base, said bracket and said 0 table being rotatable about said threaded means, said threaded means having other threaded means associated therewith and engageable with said bracket for clamping said bracket against REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 45,981 Doane Jan. 24, 1865 126,580 Sanford May 7, 1872 149,952 Patullo Apr. 21, 1874 1,839,647 Combs Jan. 5, 1932 2,074,976 Beardsley Mar. 23, 1937 2,165,002 Ocenasek July 4, 1939 2,327,239 Bartlett Aug. 17, 1943 2,453,899 Gaines Nov. 16, 1948 FOREIGN PATENTS Number Country Date 411,927 Great Britain June 21, 1934 243,404 Switzerland Dec. 16, 1946 

